Tanning process



, JOSEPH M. Bnow v, or AUSTIN, ARKANSAS.

' TANNING rnoonss.

No Drawing.

To all whom it may concern:

Be it known that I, JOSEPH 'M. BR WN, a citizen of the United States, residing at Austin, in the county of Lonoke and State of Arkansas, have invented a new and useful Tanning Process, of which the following 15 a specification.

This invention relates to a process of tanning hides.

The objects of the invention are to provide a tanning process which is suitable for all grades of leather, which is quick and sure in its results, yet not expensive, which produces a leather of great durability, high finish and desirable color and as nearly waterproof as possible, and which may be carried out by a person unskilled in the art of tanning so as to .produce a uniform product.

To attain these objects, I follow the process now to be described.

First the dry hide is soaked in water until perfectly soft and well washed; then the loose fat or flesh is removed. The hide must now undergo depilation or unhairing, which is accomplished by using a concentrated lnne solution. Into enough water to cover the hide, sufficient slaked lime is put to form a thin batter. When this is cool, the hideis',

dipped three or four times to makesure the lime reaches every part of 1t then is placed in the batter and allowed to remain until the hair slips easily. A period of 24 to 48 hours is usually sufficient.

The action of the lime on the hide is marked, causing it to become plump and swollen and atthe same time looseningthe hair so that on scraping'with a blunt knife the hair comes off readily. The lime also gives to the hide a reater firmness, which is very desirable in t e subsequent operations. When the hair slips, the hide israised out of the solution, placed on a smooth hard surface and unhaired. The lime must now be removed because it would interfere with the tanning if retained. To accomplish this, the hide is preferably put in running water for 2% to 48 hours, though still water may be used if it is changed three or four times daily. When the hide feelssoft and rough to the hand which is passed over thegram side, the lime has been removed. The hide is now ready for tanning. I 7

Into enough water to cover the hide I dissolve cutch in the proportion of 1 pound of cutch to 10 pounds of green hide. The solution is preferably mixed in a tin or gal- Specification of Letters Patent. I

green hide.

tented p as, 1919.

Application filed April Q, 1919. Serial N0.'28'7,44 9.

vanized vessel and strained into a Wooden half as much zinc sulfate is used as cutch,that

is one-half pound to every 10 pounds of thoroughly tanned. This condition may be ascertained by finding when the hide becomes a uniform color throughout its greatest thickness. d

The hide should now be taken out of the solution and rinsed in clear water. This done, it should be spread out on a smooth surface and oiled on both sides with .a mixture of neats foot oil and fish oil or else common tanners oil. The hide is left in this position The skin is left in the bath until until the oil has struck in and the hide i almost dry; then the wrinkles are ironed out of the grain side of the leather by one of the implements customarily used for this purpose and the flesh side is smoothed with sand .paper or equivalent means. The leather is now ready for the market.

When making sole leather, the above method is followed except that the oil is applied lightly on the grain' side only.

When tanning all large hides,weighing as much as 15 pounds or more green, only onehalf the required amount of cutch and white vitriol is used when the hides are put for the 1 first time in the tanning bath. On the second day, the hides should be taken; out and repelted; then the solution is strengthened with the undissolved portion of-the cheini- The process cial apparatus, and has the further. virtue ofbeing rapid; The cutch is an activetanning' agent, while the white vitriol aids greatly in producing a'firm, tough leather, especially desirable for harness or sole purposes.

Havin described my invention what is claimed is p '1. That method of tanning which consists in dipping a hide into a bath at succesiio sive intervals, said bath consisting of a s0lu-.

" tion of ciitch in water, addingwhite vitriol the proportion of one pound of c'u'tc'h to ten i v H to the bath, and leaving the hide therein until completely tanned.

2. That method of tanning which consists in taking a quantity of water sufficient to cover a hideydissolving cutch in the water in *pounds of'hide, dipping the hide'into said solution. at successive intervals, adding to the-solution powdered white vitriol of onehalf the weight of the cutch, andreturning the; hide to the solution iintil com p letely tanned; V

In testimony,'that I claim the foregoing as my o-w'n, I have hereto afixed my signa- 15V tnre n the presence of two witnesses.

his mark 

